JP2001289921A - Insulation inspection device for small spindle motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily and surely inspect insulation of a small spindle motor having an annular core for applying an insulating coating to the whole surface in the stage of a motor subassembly so as to prevent the peeling-off of the insulating coating as much as possible. SOLUTION: This insulation inspection device uses a conductive conical member for forming sharp sword-like blades 21 along an inclined face on a conical surface as a probe 20. This probe 20 is inserted into a stator coil part 10 for winding a three-phase stator coil 12 on the annular core 11 for applying the insulating coating to the whole surface. The insulating coating applied to an inner peripheral surface of the annular core 11 is cut in a sword-cut shape by the sword-like blades 21 to thereby bring the probe 20 direct contact with the annular core 11. Insulation resistance between the probe 20 and the three-phase stator coil 12 is measured in this state by an insulation resistance meter 24 to judge the existence of insulation failure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulation inspection device for a small spindle motor used as a drive source of a portable electronic device.

[0002]

2. Description of the Related Art Before a small spindle motor is shipped from a factory, various inspections are performed in addition to a motor rating test. These tests include an insulation test. In a small spindle motor, the motor coil is naturally coated with an insulating coating, but the core around which the motor coil is wound is also coated with an insulating coating.
In general, the core of a small spindle motor is a substantially ring-shaped part having a diameter of several centimeters and having nine or twelve magnetic poles protruding at equal intervals on the outer peripheral surface. Conventionally, after masking the inner peripheral surface or the outer peripheral surface of the core, an insulating agent is sprayed to apply an insulating coating to the core. The reason why the insulation coating is applied partially rather than entirely is that the inner or outer peripheral surface of the core is not in contact with the coil, but it is necessary to support the core on these surfaces during coating. This was because of the manufacturing process.

Conventionally, motor insulation inspection of a small spindle motor has been performed using, for example, an insulation resistance meter. That is, the insulation resistance between the connector terminal of the completed motor and the core is measured by an insulation resistance meter, and compared with a reference value to determine whether the product is good or defective. In this case, it was convenient for the core to have a part without an insulating coating. The insulation test can be performed simply by bringing one test terminal of the insulation resistance meter into contact with the connector terminal of the finished motor and the other test terminal by contacting the inner or outer peripheral surface of the core without insulation coating. Because they could do it. The connector terminal is a connector terminal to which an end of a motor coil is connected.

[0004] In recent years, since small spindle motors have been widely used as a drive source of a rotary drive device for a magnetic medium, demands for quality improvement of small spindle motors have become severe. Since the trace gas contained in the core is also harmful to the magnetic medium, one of the requirements is to contain it. Therefore, the entire surface of the core was coated by insulation, and the coating method was completed. However, since the entire surface of the core was coated with insulation, a simple insulation test using a conventional insulation resistance meter could not be performed.

[0005]

An object of the present invention is to easily and reliably inspect the insulation of a small spindle motor provided with an annular core having an insulating coating on the entire surface at the stage of a semi-finished motor. In addition, an object of the present invention is to provide an insulation inspection device that performs insulation coating as little as possible.

[0006]

A conductive conical member having a sharp sword-shaped blade formed on a conical surface along an inclined surface is used as a probe. This probe is inserted into a stator coil component in which a three-phase stator coil is wound on an annular core having an entire surface coated with an insulating coating, and the insulating coating applied to the inner peripheral surface of the annular core by the sword-shaped blade is applied. A cut was made in the shape of a sword to allow direct contact between the annular core and the probe. In this state, the insulation resistance between the probe and the three-phase stator coil was measured by an insulation resistance meter to determine the presence or absence of insulation failure.

Since the probe has a conical shape, the stator coil component can be easily inserted into and removed from the probe, and at the same time, a sword-like blade formed on the surface of the probe has a blade inside the annular core of the stator coil component. The effect of cutting the insulating coating on the peripheral surface easily and with a minimum necessary scratch was obtained. These effects became more remarkable by forming three sword-shaped blades at equal intervals.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the embodiment of the insulation inspection apparatus for a small spindle motor according to the present invention, an inspection object is a semi-finished motor before combining a stator and a rotor. The semifinished motor includes at least a stator coil component 10. As shown in FIG.
The phase coil 12 (U), the V-phase coil 12 (V), and the W-phase coil 12 (W)
(U), V-phase salient poles 12 (V) and W-phase salient poles 11 (W).

The small spindle motor insulation inspection apparatus according to the present invention comprises a probe 20 and an insulation resistance meter 24. The probe 20 is, as shown in FIGS.
It is composed of a conductive conical member having a cylindrical base 23 and a conical body 22. A sharp sword-shaped blade 21 is formed on the surface of the cone portion 22 along the inclined surface. As can be seen from FIG.
The blades 21a, 21b, and 21c are arranged at regular intervals.

In the insulation inspection of a small spindle motor, a semi-finished motor, that is, a stator coil part 10 to be inspected is inserted into a conical portion 22 of a probe 20 composed of a conductive conical member, and is appropriately pressed. . Then, three sharp sword-shaped blades 21 a, 21 b, 21 c formed on the surface of the cone portion 22 of the probe 20 are provided on the inner peripheral surface of the annular core 11 of the stator coil component 10. The coating is cut into a sword so that the annular core 11 and the probe 20 come into direct contact. In this state, the insulation resistance between the probe 20 and the three-phase stator coil 12 is measured by the insulation resistance meter 24 to determine the presence or absence of insulation failure.

After completion of the insulation inspection, the inspected stator coil component 10 is removed from the probe 20. Since the probe 20 constituting the insulation inspection apparatus according to the present invention has a conical shape, the stator coil component 10 can be easily removed from the probe 20. Moreover, the flaws left on the inner peripheral surface of the annular core 11 of the stator coil component 10 due to the inspection are extremely thin like a sword flaw. Therefore, the insulating effect of the insulating coating on the inner peripheral surface of the annular core 11 is not substantially affected at all.

[0012]

According to the present invention, the insulation inspection of a small spindle motor provided with an annular core having an insulation coating on the entire surface can be easily and reliably performed at the stage of a semi-finished motor.
In addition, there has been provided an insulation inspection apparatus that performs insulation coating as little as possible. That is, since the probe of the insulation inspection device according to the present invention is formed of a conical conductive member, the stator coil component can be easily inserted into and removed from the probe, and at the same time, a sword formed on the surface of the probe. The effect that the blade having the shape of a circle cuts the insulating coating on the inner peripheral surface of the annular core of the stator coil component easily and with the minimum necessary scratches was obtained. Therefore, the annular core after the inspection did not have any scratches that would reduce the insulating effect of the insulating coating.

[Brief description of the drawings]

FIG. 1 is a plan view showing a state in which a stator coil component to be inspected is inserted into a probe according to an embodiment of the present invention.

FIG. 2 is a side view including a partial cross-sectional view of a state where a stator coil component to be inspected is inserted into a probe according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Stator coil component 11 Magnetic pole of stator core 11 (U), 11 (V), 11 (W) Salient pole of each layer of stator core 12 Stator coil 12 (U), 12 (V), 12 (W) Stator coil of each layer 13 Connector terminal of motor coil 20 Probe 21, 21 a, 21 b, 21 c Sword-shaped blade 22 Conical part 23 Column base 24 Insulation resistance meter

Claims (2)

[Claims] 1. A probe of a conductive conical member having a sharp sword-shaped blade formed on a conical surface along an inclined surface,
A probe in which a stator coil component in which a three-phase stator coil is wound around an annular core having an entire surface coated with an insulating coating is inserted into the inner peripheral surface thereof to a position where the insulating coating is cut in a nick shape by the sword blade. And an insulation resistance tester for measuring insulation resistance between the probe and the three-phase stator coil. 2. The insulation inspection device for a small spindle motor according to claim 1, wherein three sword-shaped blades are formed at equal intervals.